Unlike most self-driving cars, the Audi does not have cameras, radars and other clunky devices on the roof. So how does the car work?

Before Audi's demonstration at the Consumer Electronics Show, the company put up a bunch of sensors -- which are blue and about the size of a paint can -- along the car's route. The car uses Wi-Fi to communicate with them.

"We want to make sure we can bring this technology to the market as fast as possible," says Annie Lien, who is a part of Audi's electronic research laboratory. Audi's game plan is to focus on self-parking technology so they can license it to other carmakers.

Self-driving cars are a quest that carmakers from Hundai to Volvo are pursuing, but each has a different business strategy. Toyota has its fully autonomous car on display at CES. It's a research vehicle that has a thick black racks on the roof and the grill which are filled with sensors and cameras.

"A full autonomous will come sometime in the future. We don't know when that is, but in the meantime, we're looking to bringing more technologies, providing products that are safer, as we go along," says Jim Pisz, corporate manager for North American business strategy at Toyota.

Among the safety features Toyota gleaned in its pursuit of a fully-autonomous car? A car that will stay in its lane if its driver falls asleep.

That feature is available as part of a $6,000 advanced technology package in its Lexus LS460.